ABSTRACT
BACKGROUND: The coronavirus disease 2019 (COVID-19) disproportionately affected African Americans (AA) and Hispanics (HSP). AIM: To analyze the significant effectors of outcome in African American patient population and make special emphasis on gastrointestinal (GI) symptoms, laboratory values and comorbidities. METHODS: We retrospectively evaluated the medical records of 386 COVID-19 positive patients admitted at Howard University Hospital between March and May 2020. We assessed the symptoms, including the GI manifestations, comorbidities, and mortality, using logistic regression analysis. RESULTS: Of these 386 COVID-19 positive patients, 257 (63.7%) were AAs, 102 (25.3%) HSP, and 26 (6.45%) Whites. There were 257 (63.7%) AA, 102 (25.3%) HSP, 26 (6.45%) Whites. The mean age was 55.6 years (SD = 18.5). However, the mean age of HSP was the lowest (43.7 years vs 61.2 for Whites vs 60 for AAs). The mortality rate was highest among the AAs (20.6%) and lowest among HSP (6.9%). Patients with shortness of breath (SOB) (OR2 = 3.64, CI = 1.73-7.65) and elevated AST (OR2 = 8.01, CI = 3.79-16.9) elevated Procalcitonin (OR2 = 8.27, CI = 3.95-17.3), AST (OR2 = 8.01, CI = 3.79-16.9), ferritin (OR2 = 2.69, CI = 1.24-5.82), and Lymphopenia (OR2 = 2.77, CI = 1.41-5.45) had a high mortality rate. Cough and fever were common but unrelated to the outcome. Hypertension and diabetes mellitus were the most common comorbidities. Glucocorticoid treatment was associated with higher mortality (OR2 = 5.40, CI = 2.72-10.7). Diarrhea was prevalent (18.8%), and GI symptoms did not affect the outcome. CONCLUSION: African Americans in our study had the highest mortality as they consisted of an older population and comorbidities. Age is the most important factor along with SOB in determining the mortality rate. Overall, elevated liver enzymes, ferritin, procalcitonin and C-reactive protein were associated with poor prognosis. GI symptoms did not affect the outcome. Glucocorticoids should be used judiciously, considering the poor outcomes associated with it. Attention should also be paid to monitor liver function during COVID-19, especially in AA and HSP patients with higher disease severity.
ABSTRACT
Bovine mastitis is a costly disease in the dairy industry and does not always respond to antibiotic treatment. The major components of terpeneless, cold-pressed Valencia orange oil - citral, linalool, decanal and valencene - were examined as potential alternative treatments for Staphylococcus aureus-associated mastitis. The minimum inhibitory concentration (MIC) of all four components against S. aureus was determined after incubation for 24 h. Growth inhibition assays were performed for all effective components on S. aureus for either a 3 h or 72 h treatment. These components were tested for the ability to disrupt pre-formed S. aureus biofilms after 24 h of treatment by measuring absorbance at 540 nm. Cytotoxicity against immortalized bovine mammary epithelial (MAC-T) cells was measured using an MTT assay following a 1 h exposure. Only concentrations below the 50 % cytostatic concentration (CC50) were used in an adherence and invasion assay of S. aureus on MAC-T cells, and for measurements of virulence and biofilm gene expression via qPCR. The MICs of citral and linalool were 0.02 % and 0.12 %, respectively, but decanal and valencene were ineffective. Citral and linalool were capable of inhibiting growth of S. aureus after 24 h at their MIC values and inhibited pre-formed biofilms of S. aureus . The concentrations below the CC50 were 0.02 % for citral and 0.12 % for linalool. These concentrations inhibited the adhesion and invasion ability of S. aureus and downregulated virulence genes. Only 0.12 % linalool downregulated the expression of S. aureus biofilm-forming genes. These components should be considered for further in vivo study.
